Treatments for toxoplasmosis in pregnancy

No randomised trials identified on treatments for toxoplasmosis in pregnancy.

Toxoplasmosis is a widespread parasitic disease that usually causes no symptoms. However, infection in pregnant women may cause infection in the baby, resulting in possible mental disability and blindness. The risk to the baby is related to the gestational age at the time of infection. The greatest risk of transmission to the baby is during the third trimester, but disease is most severe when it is acquired during the first trimester. In some countries pregnant women are screened for toxoplasmosis by testing for antibodies to the parasite. Women who have no antibodies at the beginning of pregnancy but develop antibodies during pregnancy are considered to have active infection and their babies are at increased risk of toxoplasmosis. Antibiotics (spiramycin and sulphonamide) may be prescribed to try to reduce the risk of mother-to-child transmission, and to reduce the severity of infection in the baby; however these drugs have potential adverse toxic effects. Other countries feel the likelihood of success is too low and to risk the potential adverse effects of the drugs on the baby. Screening programmes will have no impact unless the interventions that are given as a result actually reduce congenital infection and improve infant outcomes. Hence this review sought evidence from randomised controlled trials on the effects of treatments on women who showed signs of toxoplasmosis infection during pregnancy. No randomised controlled trials were identified, so there is no sound evidence on which to base screening and treatment programmes; such evidence is needed and trials of adequate size should be undertaken.

Authors' conclusions: 

Despite the large number of studies performed over the last three decades we still do not know whether antenatal treatment in women with presumed toxoplasmosis reduces the congenital transmission of Toxoplasma gondii. Screening is expensive, so we need to evaluate the effects of treatment, and the impact of screening programmes. In countries where screening or treatment is not routine, these technologies should not be introduced outside the context of a carefully controlled trial.

Read the full abstract...
Background: 

Toxoplasmosis is a widespread parasitic disease and usually causes no symptoms. However, infection of pregnant women may cause congenital infection, resulting potentially in mental retardation and blindness in the infant.

Objectives: 

The objective of this review was to assess whether or not treating toxoplasmosis in pregnancy reduces the risk of congenital toxoplasma infection.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (February 2006). We updated this search on 1 October 2009 and added the results to the awaiting classification section.

Selection criteria: 

Randomised controlled trials of antibiotic treatment versus no treatment of pregnant women with proven or likely acute Toxoplasma infection, with outcomes in the children reported. We also inspected relevant reports of less robust experimental studies in which there were (non randomly allocated) control groups, although it was not planned to include such data in the primary analysis.

Data collection and analysis: 

Reports of possibly eligible studies were scrutinised by two investigators.

Main results: 

Out of the 3332 papers identified, none met the inclusion criteria.